I have the same type of issue with some of my users in the office.... One user has Adobe CC 2017 (with Indesign) and another user has InDesign 2015 and does not have the Creative Cloud app. When the user with the 2017 version tries to open 2015 files, links are broken and there are gray boxes with an "X" in them where certain pictures should be. Also, the file opens as "Untitled" instead of what the file was actually named and saved as.

They need to be able to collaborate using 2 different versions of InDesign. Please help!